妖怪ミステリー is an iPhone game developed by MASK LLC. that challenges players to solve the mysteries of yokai, supernatural creatures from Japanese folklore. In this game, players will encounter various yokai who appear before them and set up puzzles and challenges. The objective is to unravel the mysteries of these yokai and uncover their true motives.

The game offers a completely free playing experience, allowing players to enjoy all the puzzles without any cost. It also welcomes gameplay from content creators, with no need for permission.

To play 妖怪ミステリー, players need to follow a simple set of instructions. First, they need to review the question content. Then, they must search for the correct answer within the provided image. Once they have found the correct spot, they can tap on it and press the "決定" button at the bottom of the screen. Successfully solving a puzzle will lead players to the next challenge.